The present invention relates generally to method and apparatus for use in the manufacture of paper and/or board products and, more particularly, to method and apparatus wherein a fibrous base material such as, for example, waste paper, is first admixed with water in a pre-soaking device to form a fibrous mixture which is then transported to a pulper device wherein additional water is added to form an aqueous fibrous suspension. The aqueous fibrous suspension is then purified, treated further and thereupon transmitted to subsequent paper or board fabricating machines for further finish processing and fabrication into the desired paper or board product.
In the manufacture of paper or board products from fibrous base materials, particularly from waste paper or the like, the fibrous base materials during processing are defibrated which results in the fibers being released from the structures which cohere with and about them. The fibers then accumulate as a suspension in water and serve as the base material for the respective paper or board processing apparatus.
Defibering, even when waste paper is used as the base material, is effected in a pulper, i.e., a large container which includes an agitator which serves to violently agitate a mixture of waste paper and water so as to produce the desired fibrous suspension. A pulper of the type heretofore used, due in large part to the degree of agitation required, and the attendant technical requirements therefore, requires the expenditure of substantial amounts of energy in order to operate efficiently. Consequently, such apparatus is extremely expensive to manufacture and maintain.